Extension bit-holder.



W. A. PEUK.

EXTENSION BIT HOLDER.

APPLICATION FILED MAY 10, 1909.

954,046, Patented Apr. 5, 1910.

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WILLIAM A. PECK, JERSEY CITY, NEW JERSEY.

EXTENSION BIT-HOLDER.

Specification of Letters Patent. A

Patented Apr. 5, 1910.

Application filed May 10, 1909. Serial No. 495,164.

To all whom it may concern:

Be it known that I, WILLIAM A. Peek, a citizen of the United States,residing at Jersey City, in the county of Hudson and State of NewJersey, have invented a certain new and useful Improvement in ExtensionBit-Holders, of which the following is a specification.

The invention relates to holders for augerbits by which the bit-shaftmay be extended, and the object of the invention is to provide a simpleand economical construction by which the diameter of the chuck or bodymay be greatly reduced without impairing strength, and in which thebit-shank may be held reliably for service and positively locked againstaccidental withdrawal.

The invention consists in certain novel features and details ofconstruction by which the above objects are attained, to be hereinafterdescribed.

The accompanying drawings form a part of this specification and show theinvention as it has been carried out in practice.

Figure l is an elevation of the improved holder with a bit therein. Fig.2 is a similar view at a right angle to Fig. 1. Fig. 3 is a verticalaxial section, partly in elevation, corresponding to Fig. 1. Fig. 4: isa similar sectional view showing the body of the holder alone. Fig. 5 isan end view of the holder with a bit therein, the shaft of the latterbeing shown in cross-section. Fig. 6 is a transverse section taken onthe line 66 in Fig. 4, and partly in plan or end view.

Fig. 7 is an end view of the segmental retainer. Fig. 8 is acorresponding side view partly in longitudinal section.

Similar letters of reference indicate the same parts in all the figures.

A is the body or chuck of the holder, A

the shaft, and A the squared tapered shank by which it is secured in thechuck of a bitbrace or other turning means. The body A is cylindricaland bored and tapped interiorly at the outer end for a short distance asat B, and the cavity thus formed continued axially as a rectangulartapered socket C terminating in a square hole D serving with the taperedportion G to receive the shank F2 of a bit F and compel it to rotatewith the holder.

M is the retainer consisting of a tube exteriorly threaded. at one end,as at M and having a portion of one side removed throughout its lengthto form a longitudinal slit or opening m, the whole being in effect asegmental screw-plug matching the internal threads B of the holder, andturned by the knurled or otherwise roughened portion M beyond the screwthreads M In end view the retainer shows a curve somewhat more than asemicircle, and the opening on is of sufficient width to admit the shaftF of the auger F, up to the capacity of the holder.

In inserting the bit, its shank F is set in the socket C, the retaineris then applied to the shaft F to in'close the latter, its threadsengaged with the internal threads of the body A, and it is turned firmlyhome with its inner end in strong contact with the shoulder F at thejunction of the shaft F and shank F of the auger-bit. Thus positionedthe bit is locked in the socket and cannot be withdrawn without removingthe retainer.

Preferably the angles of the tapered socket O are continued as grooves 0across the screw-threaded portion B of the body, as shown in Figs. 4, 5and 6, and these grooves are preferably of greater angular opening thanthe 90 of the socket, so that when serving with a bit of large size suchgrooves in addition to the socket itself, but

-with the side faces of the shank are out of contact with the adjacentside faces of the groove, thus avoiding distortion or other injury tothe threads due to torsional strains. The inner edge of the retainer isrounded as at m the better to match the corre' sponding shoulder F andinsure rigidity.

It will be noted that the body A may be as small in diameter as is,compatible with strength and range of shank sizes, and by inserting theretainer on the inside of the body, permitted by the relatively smalldiameter of bit-shaft, the bit is securely locked in place with noportion of the chuck or locking means extending beyond the circumferenceof the body; thus constructed the body may follow in the cut of a muchsmaller bit than is usual in devices of this character. In electricinstallations a 5/8 inch hole is very desirable for certain fixtures,the improved holder may be made to follow a bit of that or even smallersize without sacrificing strength.

The holder may be of any desired length, or two or more may be coupledto produce extreme lengths if necessary. The longitudinal edges of thecut or opening m offer additional gripping surfaces for the fingers inremoving or inserting the retainer and also provide a fiat face for theapplication of a wrench if desired.

Modifications may made in the forms and proportions within wide limits,and the chuck composed of the body and retainer may be made part of abrace or similar tool. The grooves 0 may be omitted, depending on thetapered socket-portion of the body alone for engagement with thebit-shank.

I claim 1. In a tool of the character set forth, a body portionscrew-threaded internally and having a rectangular tapered socket withthe angles of such socket continued as grooves across suchscrew-threads, of greater angular opening than the 90 of the socket incombination with a segmental cylindrical retainer, greater than asemi-circle screwthreaded externally to engage the threads of said bodyand extended beyond the end of the body portion, and adapted to servewith the latter and with the shaft and shank of an auger-bit inserted insaid socket, isiublstantially as and for the purposes speci- 2. In atool of the character set forth, a

body portion screw-threaded internally and having a rectangular taperedsocket with the angles of such socket continued as angular groovesacross such screw-threads, the angles of the side faces of such groovesbeing greater than those of the socket to receive the bit-shank, incombination with a segmental cylindrical retainer, screwthreadedexternally to engage the threads of said body, and adapted to serve withthe latter and with the shaft and shank of an auger-bit inserted in saidbody, substantially as and for the purposes herein specified.

3. In a tool of the character set forth, the combination of a bodyportion screwthreaded internally and having a rectangular tapered socketwith the angles of such socket continued as grooves across thescrewthreads to receive the bit shank, and a retainer co-acting with thescrew threads.

In testimony that I claim the invention above set forth I affix mysignature, in presence of two witnesses.

\VILLIAM A. IECK.

lVitnesses CHARLES R. SEARLE, RUssELL CROMBIE.

